CPU Low clock speed

One day my Computer started being extremely slow when opening a new tab, playing videos and games, etc. but it would start up just fine and work okay-ish when working within the same document or browser tab without switching.

After running memtest I concluded it must be my Memory which I promptly switched out but to no avail. I just formatted, reinstalled Windows 10, downloaded HWMonitor and noticed the following -

My CPU clock speed is extremely low. This is not exclusive to Idle mode and actually stayed at 800 MHz max even when trying to play games etc.

Now I'd like to know the reason for that before going out and buying a new CPU only to realize it was the Mainboard or a software issue all along. Is there anything I can do or diagnose further? My power settings are "balanced".

Thanks in advance!

Solution 1:

It sounds and looks a lot your CPU is being actively limited. Even though your temperature is fine at about 30 degrees you are still locked at 800MHz. To me this pretty much rules out thermal throttling as your CPU would have to be somewhere above 80 or 90.

My guess is that while you are on the "balanced" power plan it has, for whatever reason, gotten corrupted and your "Maximum processor state" has been locked at somewhere close to minimum.

Check that you have something like the image below and that "Maximum processor state" is set to 100%:

Solution 2:

Another possibility is a failed fan or clogged up heatsink. When a CPU gets too hot it throttles down to protect itself - slower clock speed means less power means less heat.